Container closure



United States Patent 3,303,955 CONTAINER CLOSURE Andrew G. Osborne andEdward A. Stassin, Richmond, Ind., assignors to Aluminum Company ofAmerica, Pittsburgh, Pa., a corporation of Pennsylvania Filed Dec. 1,1965, Ser. No. 510,855 4 Claims. (Cl. 215-39) This invention relates tothe packaging of materials that develop pressures above atmosphericpressures, and is particularly concerned with a combination of containerand closure for bottling liquids under pressure.

In the past, closure caps having crimped edges to be deformed to grip abead on the bottle and known as crown caps have been used in the sealingof bottles containing charged liquids. These caps have excelled so inholding against pressures up to 120 p.s.i. that their use has beenalmost exclusive in this field despite the fact that they can be removedonly with a prying tool and are deformed thereby so as not to provide aneffective reseal. An effective reclosure seal undoubtedly can be made ofbulky or expensive materials or in intricate designs not suitable forthe bottling industry where package costs must be competitive. The needfor an economical package capable of withstanding the pressures ofcharged liquids and providing an effective reseal has persisted for manyyears.

We have discovered that a proper answer to this problem is found in aparticular combination of cap material, thickness and condition, linerdispositon, and closure and container design.

Accordingly, it is an object of this invention to provide for thesealing and recl-osing of charged liquid packages. More particularly, itis concerned with providing an economical package for this purpose. Thespecific object of the invention is to provide an economicalcontainerclosure combination suitable for modern high speed packagingoperations and affording a pressure seal and effective reclosure.

The manner in which our invention contributes to these objectives willbe clear from the following description and the accompanying drawings,in which:

FIG. 1 is a vertical sectional view of the closure blank used in thecombination;

FIG. 2 is a partial vertical sectional view on a larger scale showinghow the closure blank is reformed on a contanier designed for ourcombination, the form of the marginal portion of the closure and linerprior to deformation being shown in dotted lines; and

FIG. 3 is a fragmentary sectional elevation view showing the finishedpackage.

The cap blank 9 is drawn from a sheet 0.008 to 0.0095 inch thick ofdeformable aluminum base alloy in the extra hard temper designated H19.As used herein the term aluminum base alloy means an alloy containing atleast fifty (50) percent by weight of aluminum. Preferably the aluminumbase alloy used to make the closure blank contains aluminum and between0.3 and 1.5 percent manganese, between 0.2 and 0.8 percent magnesium andother metals not to exceed percentages of silicon 0.6, iron 0.7, copper0.4, chromium 0.25, zinc 0.4, titanium 0.1, and in any other metal 0.05and the total of other metals 0.15. This alloy is preferred as it isreadily deformable and has good strength characteristics in the H19temper. The drawing operation provides a top panel 10 and a dependingcylindrical skirt 11, and the skirt is knurled at 12. Within the cap isa liner 13, preferably of an odorless and tasteless elastomericmaterial, such as for examle poly vinyl chloride. The liner 13 should beretained in proper position by adhering it to the top panel, and linersmade of poly vinyl chloride should be 0.028 inch thick, plus or minus0.003 inch. The drawings show the liner 13 as a disk, however, a ringtype liner would also be satisfactory.

The closure receiving finish of the container 20 includes top sealingsurface 21, a reduced annular portion or recess adjacent theretopresenting a side sealing surface 22, a radially outwardly extendingshoulder 23 below the side sealing suface and closure retaining means,such as screw threads 24, below the shoulder.

The pressure block 30 used in applying the closure to the container 20has a recess 31 and a shoulder 32. With this design, the pressure blockdeforms the marginal portion of the closure and liner from thehorizontal plane positions shown in dotted lines to that shown in fulllines in FIG. 2, while applying top pressure, to assure sealing contactover the top and side sealing surfaces 21 and 22.

Cooperating with the pressure block 30, in that it acts while the blockretains the closure under pressure, is a thread roller 33 which deformsthe skirt 11 into conformity with the threads 24.

The combination is provided with visual detection means generallyreferred to as t-amperproof means. For this purpose, the closure skirt11 includes a band 14 connected to the remainder of the skirt by anumber of frangible bridges 15, and the container has a downwardlyfacing, inwardly directed, shoulder 25. The margin of the band 14 isturned under this shoulder by means of a roller 34 acting simultaneouslywith the thread rolling operation. The band also acts to retain theliner compression and sealing efficiency. With this construction,turning of the closure to disengage the threads 24 fractures the bridges15, leaving the band engaged with the shoulder 25 to visually indicatethat the package has been opened.

Numerous advantages for pressure packaging are attributable to ourdesign.

The known advantage of top and side scaling is increased by reason ofthe relatively more extensible side seal.

The right angle bending about the top and side sealing surfaces providesa margin without irregularities and so provides uniform length of skirtin the finished closure.

Right angle bending of the closure about the reduced diameter sealingsurface causes a relatively greater elongation of the skirt.Consequently, a shallower, rnore economical closure blank may be usedfor any given finished closure length. The advantage of this for feedingof closure blanks is also an important consideration, particularly whenmodern high speed sealing machines are employed.

The design provides a reduced top panel diameter after application forany given diameter of thread formation. The effect of this is to reducebulging of the top panel by internal pressure, because the fulcrum ofsuch bulging is on a line nearer to the center of the top panel. Thisresults in a lesser loss of liner compression that otherwise would becaused by internal pressure.

In the finished closure, the knurled portion 12 of the skirt assumes aslight upward inwardly directed taper. From this, tension in theshoulder 16 formed by the pressure block 30 tends to collapse theunsupported portion of the skirt but this tendency to collapse isresisted by the knurling. It follows that residual tension in theshoulder 16 aids in maintaining liner compression on the top sealingsurface 21.

It will be understood that we have shown and described the preferredform of our invention, and that other forms thereof are contemplatedwithin the scope of the following claims.

We claim:

1. A container-closure combination for packaging materials which developpressures substantially above atmospheric pressures comprising,

a container having an upper open end presenting a top sealing surfaceand an exterior finish including an annular recess extending downwardlyfrom and adjacent to the open end and presenting a side cylindricalsealing surface, an annular outwardly extending shoulder below said sidesealing surface, a screw thread formation below said shoulder, and anannular inwardly directed shoulder below said thread formation, and

a closure having a metal thickness between 0.008 and 0.0095 inchcomposed of an aluminum base alloy in the extra hard temper, saidclosure including a top panel and depending skirt, the upper portion ofthe skirt being of lesser diameter than the portion immediatelytherebelow, a portion of the skirt below the lesser diameter portionconforming to the thread formation on the container and a bandintegrally connected with the skirt by frangible bridges around theskirt, said band having a crimped margin turned inwardly under saidinwardly directed container shoulder, and

a sealing liner of resilient deformable material underlying the toppanel of the closure and bearing on the top sealing surface contact withthe cylindrical side sealing surface on the container by said lesserdiameter portion of the closure skirt,

said lesser diameter portion of the closure skirt and said dependingmarginal portion of the liner being deformed from horizontal planepositions.

2. A container-closure combination as in claim 1 in which the aluminumbase alloy consists essentially of aluminum, between 0.3 and 1.5 percentmanganese, between 0.2 and 0.8 percent magnesium and other metals not toexceed percentages of silicon 0.6, ir-on 0.7, copper 0.4, chromium 0.25,zinc 0.4, titanium 0.1, and any other metal 0.05 and the total of othermetals 0.15.

3. A container-closure combination as in claim 1 in which said cap has aknurled portion tapering inwardly and upwardly below the lesser diameterportion and above the conforming portion.

4. A container-closure combination as in claim 1 in which the liner is afull width disk and is of an elastomeric material approximately 0.028inch thick adhered to the JOSEPH R. LECLAIR, Primary Examiner.

D. F. NORTON, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,303,955 February 14, 1967 Andrew G. Osborne et a1.

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 1, line 47, for "contanier" read container line 62, strike out"in"; column 2, line 37, for "extensible" read extensive column 3, line23, after "surface" insert and a depending marginal portion held insealing Signed and sealed this 17th day of October 1967.

(SEAL) Attest:

Edward M. Fletcher, Jr. EDWARD J. BRENNER Attesting Officer Commissionerof Patents

1. A CONTAINER-CLOSURE COMBINATION FOR PACKAGING MATERIALS WHICH DEVELOPPRESSURES SUBSTANTIALLY ABOVE ATMOSPHERIC PRESSURES COMPRISING, ACONTAINER HAVING AN UPPER OPEN END PRESENTING A TOP SEALING SURFACE ANDAN EXTERIOR FINISH INCLUDING AN ANNULAR RECESS EXTENDING DOWNWARDLY FROMAND ADJACENT TO THE OPEN END AND PRESENTING A SIDE CYLINDRICAL SEALINGSURFACE, AN ANNULAR OUTWARDLY EXTENDING SHOULDER BELOW SAID SIDE SEALINGSURFACE, A SCREW THREAD FORMATION BELOW SAID SHOULDER, AND AN ANNULARINWARDLY DIRECTED SHOULDER BELOW SAID THREAD FORMATION, AND A CLOSUREHAVING A METAL THICKNESS BETWEEN 0.008 AND 0.0095 INCH COMPOSED OF ANALUMINUM BASE ALLOY IN THE EXTRA HARD TEMPER, SAID CLOSURE INCLUDING ATOP PANEL AND DEPENDING SHIRT, THE UPPER PORTION OF THE SKIRT BEING OFLESSER DIAMETER THAN THE PORTION IMMEDIATELY THEREBELOW, A PORTION OFTHE SKIRT BELOW THE LESSER DIAMETER PORTION CONFORMING TO THE THREADFORMATION ON THE CONTAINER AND A BAND INTEGRALLY CONNECTED WITH THESKIRT BY FRANGIBLE BRIDGES AROUND THE SKIRT, SAID BAND HAVING A CRIMPEDMARGIN TURNED INWARDLY UNDER SAID INWARDLY DIRECTED CONTAINER SHOULDER,AND A SEALING LINER OF RESILIENT DEFORMABLE MATERIAL UNDERLYING THE TOPPANEL OF THE CLOSURE AND BEARING ON THE TOP SEALING SURFACE CONTACT WITHTHE CYLINDRICAL SIDE SEALING SURFACE ON THE CONTAINER BY SAID LESSERDIAMETER PORTION OF THE CLOSURE SKIRT, SAID LESSER DIAMETER PORTION OFTHE CLOSURE SKIRT AND SAID DEPENDING MARGINAL PORTION OF THE LINER BEINGDEFORMED FROM HORIZONTAL PLANE POSITIONS.